Hey,
I'm looking for a way to enable my existing Postfix/Mailman mailing list server
with HF capability- to both send, and receive PGP-signed, or encrypted email
over radio reliably, as well as have the option to have some transmissions
either re-transmitted over the Internet.
Apparently there's Winlink[1] and it's what the Americans use, however it seems
if not proprietary, then heavily locked while I'm looking for a Free software
solution, preferably over GNU Radio and affordable SDR such as LimeSDR[2]
which is what I'm trying to master at the moment. Unfortunately, I couldn't as
much as find a reference protocol, anything, really- to suggest how I would
typically approach this- what bands, modes, encodings are used to transmit
email over the radio.
Are there any existing GNU Radio-operated email servers and/or networks I could
use for reference and future collaboration? I'm heavily invested in the idea of
hardening my email infrastructure in case of an emergency, and if Internet goes
down in my country, I still wish that my server would remain operation over the
radio.